As I understand, you mean 'How much voltage can be possible to Vdd pin', right?
It said Vdd max is 3.8[V] in document "K20P144M120SF3.pdf"
I'm not sure what 'danify' means.
So I think MK20's absolute maximum voltage is 3.8[V]. - datasheet page 8
By the way, in my perspective, 5[V] tolerable means not acceptable, just can take.
IMO, Avoiding input voltage higher than Vdd is a better choice. - Just opinion :smileyhappy:
Good day //